1. Field of the Invention
The present invention relates to a V-type internal combustion engine. More particularly, the present invention relates to a V-type internal combustion engine for a motorcycle.
2. Description of the Relevant Art
Several structures for V-type internal combustion engines are known. For example, Japanese Unexamined Patent Application Publication No. 2000-120410 discloses one structure for a V-type internal combustion engine 100, as illustrated in FIG. 6.
The V-type internal combustion engine 100, in accordance with the background art, has a pair of cylinder blocks 102 provided in a V-shape. A crankcase 103 to is attached to the cylinder blocks 102. A transmission case 104 is provided on a rear side of the crankcase 103, in a connected row arrangement. The crankcase 103 and the transmission case 104 are formed so as to be continuous or integral.
In such a conventional V-type internal combustion engine 100, a continuous portion A of the upper end portion of the crankcase 103 and the upper end portion of the transmission case 104 is formed to be almost horizontal. Consequently, as shown in FIG. 7, a gap G is formed between the continuous portion A and the lower end portion of the cylinder block 102 positioned on the rear side. The gap G creates a problem in that water, or the like, will easily accumulate in the gap.
When water accumulates in the gap G, the surface of the crankcase 103 and the surface of the transmission case 104 are affected. For example, it is possible that rust or corrosion will gather. To address the rust concern, in an American-type motorcycle, the surface of the crankcase 103 and that of the transmission case 104 are plated. However, accumulated water will still stain the plating and leave a conspicuous and undesirable mark.
The staining problem is exacerbated when the size of a clutch of the motorcycle is increased to handle an increased output power of the V-type internal combustion engine 100. The increased clutch size requires the size of the transmission case 104 to be accordingly increased. As a result, the stain in the surface in the vicinity of the gap G becomes more conspicuous.
It is an object of the present invention to address one or more of the drawbacks associated with the background art.
An object of the present invention is to provide a V-type internal combustion engine capable of preventing a stain in a crankcase and a transmission case by smoothly exhausting water, or the like, dropped between the crankcase and transmission case and a cylinder block.
These and other objects are accomplished by a V-type internal combustion engine comprising: a crankcase; a pair of cylinder blocks attached to said crankcase, wherein said pair of cylinder blocks form a V shape; and a transmission case provided on a side of said crankcase, wherein said crankcase and said transmission case are joined by a continuous portion, and wherein an uppermost portion of said transmission case is positioned higher than an uppermost portion of said crankcase.
Further, these and other objects are accomplished by a motorcycle comprising: a V-type internal combustion engine including: a crankcase; a pair of cylinder blocks attached to said crankcase, wherein said pair of cylinder blocks form a V shape; and a transmission case provided on a side of said crankcase, wherein said crankcase and said transmission case are joined by a continuous portion, and wherein an uppermost portion of said transmission case is positioned higher than an uppermost portion of said crankcase.
Moreover, these and other objects are accomplished by a vehicle comprising: a V-type internal combustion engine including: a crankcase; a pair of cylinder blocks provided in a V shape attached to said crankcase; and a transmission case provided on a rear side of said crankcase in a connected row arrangement, wherein said crankcase and said transmission case are formed continuously and an upper end portion of said transmission case is positioned so as to be higher than an upper end portion of said crankcase, thereby tilting the upper front portion of said crankcase downward.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.